Handheld Propulsion Assembly

ABSTRACT

A handheld propulsion assembly includes at least one propulsion subassembly. In the propulsion subassembly, pivot and hinge mounts are disposed respectively on upper and lower surfaces of a floatable board member, a crank shaft is pivotably mounted on the pivot mount about a pivot axis, a crank arm extends radially from the crank shaft, and a blade is hinged to the hinge mount. When a driven portion of the crank arm is driven to swing back and forth, the floatable board member is correspondingly moved forward and backward. The blade is angularly movable about a hinge axis between an unfolded position, where the blade has a maximized propelling force, and a folded position, where the blade has a minimized propelling force.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from Taiwanese application no. 104201568, filed on Jan. 30, 2015, the disclosure of which is incorporated in its entirety herein by reference.

FIELD

The disclosure relates to a handheld propulsion assembly, more particularly to a handheld propulsion assembly by which a watercraft can be propelled in a force-saving manner.

BACKGROUND

A conventional paddle includes an elongated shaft, a blade at a lower end of the elongated shaft, and a handle at an upper end of the elongated shaft. A paddler can use the paddle to propel a watercraft, such as a canoe, by inserting the blade into water and then pushing or pulling the blade through water in each paddle stroke. For propelling the watercraft, the paddler must exert a relatively large force.

SUMMARY

Therefore, an object of the disclosure is to provide a handheld propulsion assembly by which a paddler can propel a watercraft in a force-saving manner.

According to the disclosure, a handheld propulsion assembly for watercraft includes at least one propulsion subassembly which includes a floatable board, a pivot mount, a crank shaft, a crank arm, a hinge mount, and at least one blade. The floatable board member is elongated in a forward-rearward direction and has upper and lower surfaces. The pivot mount is disposed on the upper surface of the floatable board member and has a pivot bearing surface defining a pivot axis. The crank shaft has a pivoted end and a connected end opposite to the pivoted end. The pivoted end is pivotably mounted on the pivot mount about the pivot axis and is in frictional engagement with the pivot bearing surface. The crank arm extends from the connected end in a radial direction relative to the crank shaft, and has a driven portion opposite to the connected end such that when the driven portion is driven to swing back and forth, the floatable board member is correspondingly moved forward and backward due to the frictional engagement between the pivot bearing surface of the pivot mount and the pivoted end of the crank shaft. The hinge mount is disposed on the lower surface of the floatable board member and defines a hinge axis. The blade is hinged to the hinge mount and is angularly movable about the hinge axis between an unfolded position, where the blade has a maximized propelling force, and a folded position, where the blade has a minimized propelling force.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiments with reference to the accompanying drawings, in which:

FIG. 1 is an exploded perspective view of a propulsion subassembly of a handheld propulsion assembly according to a first embodiment of the disclosure;

FIG. 2 is a fragmentary side view of the propulsion subassembly shown in FIG. 1 in an assembled state;

FIG. 3 is similar to FIG. 2 but with blades in a folded position;

FIGS. 4 to 6 illustrate the handheld propulsion assembly according to the first embodiment in use;

FIG. 7 shows a modified configuration of the propulsion subassembly according to the first embodiment;

FIG. 8 is an exploded perspective view of a propulsion subassembly of a handheld propulsion assembly according to a second embodiment of the disclosure;

FIG. 9 is a fragmentary side view of the propulsion subassembly shown in FIG. 8 in an assembled state;

FIG. 10 is similar to FIG. 9 but with blades in a folded position;

FIG. 11 is an exploded perspective view of a propulsion subassembly of a handheld propulsion assembly according to a third embodiment of the disclosure;

FIGS. 12 to 14 illustrate the handheld propulsion assembly of the third embodiment in use;

FIG. 15 illustrates a handheld propulsion assembly according to a fourth embodiment of the disclosure in use;

FIG. 16 is an exploded perspective view of a propulsion subassembly of a handheld propulsion assembly according to a fifth embodiment of the disclosure;

FIG. 17 is a perspective view of the propulsion subassembly shown in FIG. 16 in an assembled state;

FIG. 18 is a top view of a blade of the propulsion subassembly of the fifth embodiment; and

FIG. 19 is similar to FIG. 18 but with the blade in a folded position.

DETAILED DESCRIPTION

Before the disclosure is described in greater detail, it should be noted that like elements are denoted by the same reference numerals throughout the disclosure.

With reference to FIGS. 1 and 4, a handheld propulsion assembly according to a first embodiment of the disclosure is used for propelling a watercraft 9, such as a canoe, and includes at least one propulsion subassembly 10.

The propulsion subassembly 10 includes a floatable board member 1, a pivot mount 20, a crank shaft 23, a crank arm 2, a hinge mount 13, and at least one blade 32.

The floatable board member 1 is elongated in a forward-rearward direction (X), and has upper and lower surfaces 11, 12. The pivot mount 20 is disposed on the upper surface 11 of the floatable board member 1, and has a pivot bearing surface 201 defining a pivot axis (P). The hinge mount 13 is disposed on the lower surface 12 of the floatable board member 1, and defines a hinge axis (H). In this embodiment, the pivot axis (P) is oriented transverse to the forward-rearward direction (X), and the hinge axis (H) is parallel to the pivot axis (P). In addition, the floatable board member 1 and the hinge mount 13 are formed in one-piece.

The crank shaft 23 has a pivoted end 231 and a connected end 232 which are opposite to each other. The pivoted end 231 is pivotably mounted on the pivot mount 20 about the pivot axis (P), and is in frictional engagement with the pivot bearing surface 201.

The crank arm 2 extends from the connected end 232 in a radial direction relative to the crank shaft 23, and has a driven portion 221 opposite to the connected end 232 such that when the driven portion 221 is driven to swing back and forth, the floatable board member 1 is correspondingly moved forward and rearward, due to the frictional engagement between the pivot bearing surface 201 of the pivot mount 20 and the pivoted end 231 of the crank shaft 23.

In this embodiment, the driven portion 221 can serve as a handle for gripping by a paddler (see FIG. 4), and the crank arm 2 has upper and lower segments 22, 21 which are telescopically connected to each other. The lower segment 21 is connected to the connected end 232 and has a tubular end portion 212 distal from the connected end 232, and the upper segment 22 has a connected end portion 222 which is distal from the driven portion 221, and which is slidably fitted into the tubular end portion 212 so as to permit telescopic connection between the connected end portion 222 and the tubular end portion 212. The tubular end portion 212 has a plurality of through holes 214 that are linearly displaced from each other. The connected end portion 222 has a spring-loaded ball 223 configured to be snapped into a selected one of the through holes 214 for adjusting the length of the crank arm 2.

The blade 32 is hinged to the hinge mount 13, and is angularly movable about the hinge axis (H) between an unfolded position (FIGS. 2 and 5), where the blade 32 has a maximized propelling force, and a folded position (FIGS. 3 and 6), where the blade 32 has a minimized propelling force.

In this embodiment, the blade 32 is hinged to the hinge mount 13 through a hinge member 31, and has a free side edge 323 and a hinged side edge 324 which is opposite to the free side edge 323, and which is hinged to the hinge mount 13 about the hinge axis (H). When the blade 32 is in the unfolded position (see FIGS. 2 and 5), the free side edge 323 is disposed remote from the lower surface 12 of the floatable board member 1 to permit the blade 32 to have the maximized propelling force. When the blade 32 is in the folded position (see FIGS. 3 and 6), the free side edge 323 is disposed close to the lower surface 12 of the floatable board member 1 to permit the blade 32 to have a minimized propelling force.

Specifically, when a paddler sits in the watercraft 9 and grips the driven portion 221 (see FIG. 4), the length of the crank arm 2 can be adjusted to permit the floatable board member 1 to float on water. As shown in FIG. 5, when the paddler drives the propulsion subassembly 10 to move the propulsion subassembly 10 rearwardly, the blade 32 is in the unfolded position and has the maximized propelling force, thereby propelling the watercraft 9 forwardly. As shown in FIG. 6, when the paddler drives the propulsion subassembly 10 to move the propulsion subassembly 10 forwardly, the blade 32 is in the folded position and has the minimized propelling force, thereby preventing the watercraft 9 to be propelled rearwardly. Because the floatable board member 1 floats on water, the paddler can drive the propulsion subassembly 10 in a force-saving manner.

As shown in FIG. 1, the propulsion subassembly 10 further includes a stop member 33 which is connected to the hinged side edge 324 of the blade 32, and which extends along a lengthwise axis (L) that is oriented perpendicular to the blade 32 such that the stop member 33 abuts against the lower surface 12 of the foldable board member 1 once the blade 32 is moved to the unfolded position (FIG. 2).

As shown in FIGS. 1 and 4, the handheld propulsion assembly includes two propulsion subassemblies 10 each having two blades 32, two stop members 33, and two hinge members 31. The blades 32 are displaced from each other in the forward-rearward direction (X).

It should be noted that each propulsion subassembly 10 can be modified to be used by two or more paddlers. As shown in FIG. 7, two paddlers can use a modified configuration of the first embodiment to simultaneously propel the watercraft 9. In this modified configuration, the floatable board member 1 is lengthened, and each propulsion subassembly 10 includes two hinge mounts 20, two crank shafts 23, two crank arms 2, four blades 32, four stop members 33, and four hinge members 31.

FIGS. 8 to 10 illustrate a handheld propulsion assembly according to a second embodiment of the disclosure. The second embodiment is similar to the first embodiment except that, in the second embodiment, instead of the stop member 33, each propulsion subassembly 10 includes left and right side brackets 34, 35. In each propulsion subassembly 10, the blade 32 has left and right lateral edges 321, 322 which are opposite to each other in a direction of the hinge axis (H), and each of the left and right side brackets 34, 35 connects the lower surface 12 of the floatable board member 1 and a corresponding one of the left and right lateral edges 321, 322, and is configured to be collapsible. FIG. 9 shows the blade 32 in the unfolded position. When the blade 32 is displaced to the folded position, the left and right side brackets 34, 35 are displaced to a collapsed position (see FIG. 10), where each of the left and right lateral edges 321, 322 is substantially parallel to the lower surface 12 of the floatable board member 1.

In this embodiment, each of the left and right side brackets 34, 35 has pleats 341 to allow the left and right side brackets 34, 35 to be collapsible.

FIGS. 11 to 14 illustrate a handheld propulsion assembly according to a third embodiment of the disclosure for propelling a watercraft 9′ with a relatively large size. The third embodiment is similar to the first embodiment except that, in the third embodiment, each of the propulsion subassemblies 10 further includes a bearing lug 6 and an auxiliary crank member 7. As best shown in FIGS. 12 to 14, the bearing lug 6 is adapted to be mounted on a gunwale 91′ of the watercraft 9′, and has a bearing lug surface 61. The auxiliary crank member 7 has a handle segment 71, an arm segment 72, and an actuating segment 73. The handle segment 71 extends in a direction of the pivot axis (P) to terminate at a grip portion 711 and a juncture portion 712. The arm segment 72 extends from the juncture portion 712 in the radial direction to terminate at an arm end 721. The actuating segment 73 is disposed to connect the arm end 721 and the driven portion 221 of the crank arm 2, and is rotatably mounted on the bearing lug surface 61.

In addition, in each propulsion subassembly 10, the lower segment 21 of the crank arm 2 further has an impact absorbing portion 215 proximate to the connected end 232, for absorbing shock or vibration of the floatable board member 1 resulting from the swinging movement of the crank arm 2.

FIG. 15 illustrates a handheld propulsion assembly according to a fourth embodiment of the disclosure. The fourth embodiment is similar to the third embodiment except that, in the fourth embodiment, the handheld propulsion assembly further includes a post 52 and a bearing member 51. The post 52 is adapted to be mounted on a deck 92′ of the watercraft 9′. The bearing member 51 is supported by the post 52 and has left and right bearing surfaces 511, 512. Each of the propulsion subassemblies 10 further includes a coupling rod 4 extending from the grip portion 711 to terminate at a journal end 41 which is journaled on a corresponding one of the left and right bearing surfaces 511, 512. Alternatively, the grip portions 711 of the propulsion subassemblies 10 can serve as foot pedals to allow a user to propel the watercraft 9′ by pushing the foot pedals with his/her feet.

FIGS. 16 to 19 illustrate a handheld propulsion assembly according to a fifth embodiment of the disclosure. The fifth embodiment is similar to the third embodiment except that, in the fifth embodiment, a hinge mount 13′ is disposed on the lower surface 12 of the floatable board member 1, and defines a hinge axis (H) which is oriented transverse to both a direction of the pivot axis (P) and the forward-rearward direction (X). The blade 32 is hinged to the hinge mount 13′. Each propulsion subassembly 10 further includes a fin member 14 which extends downwardly from the lower surface 12 of the floatable board member 1, and which extends forwardly from the hinge mount 13′ in the forward-rearward direction (X) to terminate at a front end edge 141. The blade 32 has two blade halves 325 each having a free side edge 326 and a hinged side edge 327 which is opposite to the free side edge 326, and which is hinged to the hinge mount 13′ about the hinge axis (H). When the blade 32 is in the unfolded position (FIGS. 17 and 18), the free side edges 326 of the blade halves 325 are disposed remote from each other to permit the blade 32 to have the maximized propelling force. When the blade 32 is in the folded position (FIG. 19), the free side edges 326 of the blade halves 325 are disposed close to each other to permit the blade 32 to have a minimized propelling force.

In the fifth embodiment, each propulsion subassembly 10 includes two fin members 14, two blades 32, and two hinge mounts 13′. The fin members 14 are adapted to be disposed in water to stabilize the motion of the floatable board member 1 while the floatable board member 1 moves on water.

While the disclosure has been described in connection with what are considered the exemplary embodiments, it is understood that this disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements. 

What is claimed is:
 1. A handheld propulsion assembly for watercraft, comprising: at least one propulsion subassembly including: a floatable board member which is elongated in a forward-rearward direction, and which has upper and lower surfaces; a pivot mount which is disposed on said upper surface of said floatable board member, and which has a pivot bearing surface defining a pivot axis; a crank shaft having a pivoted end which is pivotably mounted on said pivot mount about the pivot axis, and which is in frictional engagement with said pivot bearing surface, and a connected end opposite to said pivoted end; a crank arm extending from said connected end in a radial direction relative to said crank shaft, and having a driven portion opposite to said connected end such that when said driven portion is driven to swing back and forth, said floatable board member is correspondingly moved forward and backward due to the frictional engagement between said pivot bearing surface of said pivot mount and said pivoted end of said crank shaft; a hinge mount disposed on said lower surface of said floatable board member, and defining a hinge axis; and at least one blade which is hinged to said hinge mount, and which is angularly movable about the hinge axis between an unfolded position, where said blade has a maximized propelling force, and a folded position, where said blade has a minimized propelling force.
 2. The handheld propulsion assembly according to claim 1, wherein the pivot axis is oriented transverse to the forward-rearward direction.
 3. The handheld propulsion assembly according to claim 2, wherein the hinge axis is parallel to the pivot axis.
 4. The handheld propulsion assembly according to claim 3, wherein said blade has a free side edge and a hinged side edge which is opposite to said free side edge, and which is hinged to said hinge mount about the hinge axis such that when said blade is in the unfolded position, said free side edge is disposed remote from said lower surface of said floatable board member to permit said blade to have the maximized propelling force, and such that when said blade is in the folded position, said free side edge is disposed close to said lower surface of said floatable board member to permit said blade to have a minimized propelling force.
 5. The handheld propulsion assembly according to claim 4, wherein said at least one propulsion subassembly further includes a stop member which is connected to said hinged side edge of said blade, and which extends along a lengthwise axis that is oriented perpendicular to said blade such that said stop member abuts against said lower surface of said foldable board member once said blade is moved to the unfolded position.
 6. The handheld propulsion assembly according to claim 4, wherein said blade has left and right lateral edges which are opposite to each other in a direction of the hinge axis, said at least one propulsion subassembly further includes left and right side brackets each connecting said lower surface of said floatable board member and a corresponding one of said left and right lateral edges, and each being configured to be collapsible such that when said blade is displaced to the folded position, said left and right side brackets are displaced to a collapsed position, where each of said left and right lateral edges is substantially parallel to said lower surface of said floatable board member.
 7. The handheld propulsion assembly according to claim 2, wherein the hinge axis is oriented transverse to both a direction of the pivot axis and the forward-rearward direction.
 8. The handheld propulsion assembly according to claim 7, wherein said at least one propulsion subassembly further includes a fin member which extends downwardly from said lower surface of said floatable board member, and which extends forwardly from said hinge mount in the forward-rearward direction to terminate at a front end edge.
 9. The handheld propulsion assembly according to claim 8, wherein said blade has two blade halves each having a free side edge and a hinged side edge which is opposite to said free side edge, and which is hinged to said hinge mount about the hinge axis such that when said blade is in the unfolded position, said free side edges of said blade halves are disposed remote from each other to permit said blade to have the maximized propelling force, and such that when said blade is in the folded position, said free side edges of said blade halves are disposed close to each other to permit said blade to have a minimized propelling force.
 10. The handheld propulsion assembly according to claim 1, wherein said at least one propulsion subassembly includes a plurality of said blades which are displaced from each other in the forward-rearward direction.
 11. The handheld propulsion assembly according to claim 1, wherein said crank arm has upper and lower segments which are telescopically connected to each other.
 12. The handheld propulsion assembly according to claim 11, wherein said lower segment has a tubular end portion distal from said connected end, and said upper segment has a connected end portion which is distal from said driven portion, and which is slidably fitted into said tubular end portion so as to permit telescopic connection between said connected end portion and said tubular end portion.
 13. The handheld propulsion assembly according to claim 12, wherein said tubular end portion has a plurality of through holes that are linearly displaced from each other, and said connected end portion has a spring-loaded ball configured to be snapped into a selected one of said through holes for adjusting the length of said crank arm.
 14. The handheld propulsion assembly according to claim 12, wherein said lower segment further has an impact absorbing portion proximate to said connected end.
 15. The handheld propulsion assembly according to claim 1, comprising two of said propulsion subassemblies, each further including: a bearing lug which is adapted to be mounted on a gunwale of the watercraft, and which has a bearing lug surface; and an auxiliary crank member having a handle segment extending in a direction of the pivot axis to terminate at a grip portion and a juncture portion, an arm segment extending from said juncture portion in the radial direction to terminate at an arm end, and an actuating segment which is disposed to connect said arm end and said driven portion of said crank arm, and which is rotatably mounted on said bearing lug surface.
 16. The handheld propulsion assembly according to claim 15, further comprising: a post adapted to be mounted on a deck of the watercraft; and a bearing member which is supported by said post, and which has left and right bearing surfaces, wherein each of said propulsion subassemblies further includes a coupling rod extending from said grip portion to terminate at a journal end which is journaled on a corresponding one of said left and right bearing surfaces. 